Tina the tourist goes on a trip. She starts at the origin and drives north for 10 units. Then she turns east and as she's turning her camera flies out the window and lands exactly at (0,10). She then drives 9 units east, turns and drives 8 units north. She continues this pattern of turning and driving one unit less than after the previous turn, until stopping after driving 1 unit east. She reaches for her camera only to find it missing! She activates the GPS homing device on her camera and drives back to it in a straight line. What is the equation of this line? Express your answer as ax+by=c, where a, b, and c are integers, a>0, and a is as small as possible. Please help! Thank you!